Just to throw in my two cents, if your plants are mature and don't bloom it is usually because of not getting enough light. The usual indication that the plant is mature is that the psuedobulb and leaf are about the same size every year. As far as fertilizer, I usually use the same throughout the year and fertilize less from mid November to mid February. In Pennsylvania we just don't have many days with sun then and the sun that does shine is pretty weak. You have to adjust things for some orchids that need a true rest. Jeff does have a good idea with the "grow" or high nitrogen fertilizer during spring and summer. Nutrients are a very tough thing to accurately measure results.

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